View Single Post
  #2   Report Post  
posted to rec.boats
JoeSpareBedroom JoeSpareBedroom is offline
external usenet poster
 
First recorded activity by BoatBanter: Jul 2006
Posts: 5,515
Default How to Drill Out a Broken Bolt?

wrote in message
ups.com...
I over-torqued four bolts in the lower unit of an outboard, and the
heads of three bolts broke off. I managed to remove one of the broken
bolt using a Dremel tool and a diamond grind bit. But I cannot remove
the other two broken bolts using the Dremel tool. Based on the past
posts in this newsgroup, I learn that the best option in this situation
is to drill out the broken bolts. I would like to learn the details of
the way to drill out the broken bolts. My question is:

Which size of drill bit do I need? Should it be as large as the hole
where the broken bolt is?



Call around to hardware stores and ask if they sell spiral screw extractors.
Before you jump in the car, measure the diameter of the bolt shafts you need
to remove. And, if you know the socket size that fits the heads, write that
down too.